35results about How to "Simple and mild preparation conditions" patented technology

The invention discloses an injectable thermosensitive chitosan / methylcellulose blend gel and a preparation method thereof. The gel is a physical gel, and its effective composition includes chitosan and methyl cellulose, and the weight percentages of the two are 0.25-2% and 0.25-5% respectively. The preparation method is to dissolve chitosan in an acid solution to obtain a 0.5-4wt% chitosan acid solution, and place it in an ice bath; dissolve the alkaline salt in a 0.5-10wt% methylcellulose solution, and Place in an ice bath; then slowly drop the methylcellulose salt solution into the chitosan acid solution under constant stirring to keep the solution free from turbidity, stir until the two are fully mixed, and centrifuge to remove air bubbles, then place the blended solution The gel is formed at the gel temperature. This new type of injectable temperature-sensitive gel has simple and mild preparation conditions, can avoid organic chemical reagents and other harmful substances, is suitable for the delivery of sensitive macromolecules such as protein drugs, and can also be used as an injectable medical material and tissue engineering scaffold materials.

The invention discloses a method for preparing binary and ternary high-performance composite aerogels by using iron tailings. The method comprises the following steps: mixing the iron tailings with sodium hydroxide for alkali fusion activation, cooling and washing with deionized water for solidification Liquid separation, after the washing liquid is allowed to stand for stratification, the supernatant liquid is separated from the lower mixed liquid, an acidic catalyst is added under alkaline conditions, and the wet gel is obtained by standing and aging, and the wet gel is subjected to solvent replacement and then dried under normal pressure to obtain Binary and ternary composite aerogels. The invention uses iron tailings as raw materials, has low price, wide sources, mild preparation conditions, simple process, low equipment requirements, is easy to realize industrialized preparation, and can simultaneously obtain binary and magnetic ternary composite silicon-based gas condensation; The tap density of the aerogel is less than 0.20g / cm 3 , the specific surface area of ​​binary aerogel and ternary aerogel can reach 986m, respectively 2 / g and 612m 2 / g, the adsorption capacity of methylene blue exceeds 300mg / g.

The invention relates to a preparation method of a high-density copper azide with a constrained shell, which belongs to the field of pyrotechnics. Store nanoporous copper or nanoporous copper oxide in a constrained shell, and prepare copper azide with high density through gas-solid in-situ chemical reaction with azide gas before use; avoid during operation Eliminates the dangers of traditional primary explosive production, transportation and post-pressurization. The prepared copper azide in the restrained shell has a high packing density, no danger in the filling process, safe transportation and storage, high detonation power, and a single-shot restrained shell. The dose of copper azide belongs to the sub-milligram level, and the preparation process is green and pollution-free. Adopting the method of the present invention can make packing density 1.4~3.2g / cm 3 High-density copper azide, the prepared high-density copper azide in the confined shell can detonate HNS-IV with a packing density of 75%-92% of the theoretical density and a diameter of ≥0.5mm when the dosage of the high-density copper azide in the confined shell is ≥0.4mg , CL‑20, PETN and RDX and other explosives and ignition of B / KNO 3 Wait for the gunpowder.

The invention discloses a preparation method for a flame retardant super-hydrophobic melamine sponge. The method comprises the steps that firstly silicon dioxide particles are put into a trismetyl aminomethane buffer solution with a pH value of 7.8, ultrasound treatment is carried out for 20-60 minutes, standing is carried out for 15 minutes at the indoor temperature, and then a gallotannic acid solution and a silver nitrate solution are added in sequence to obtain a mixed solution; a melamine sponge is immersed in the mixed solution, taken out after the mixed solution is stirred for 2 hours at the indoor temperature, and washed by deionized water and ethyl alcohol for several times to obtain a melamine sponge of which the surface has a micro-nano structure; finally, the melamine sponge isput into an ethyl alcohol solution which has volume concentration of 1:500-10000 and contains 1H, 1H, 2H, 2H-perfluorododecane mercaptan, stirring is carried out for 12 hours at the indoor temperature, the melamine sponge is taken out, washed by ethyl alcohol for several times and dried to obtain the super-hydrophobic melamine sponge of which water contact angle is larger than or equal to 145 degrees. The preparation method for the flame retardant super-hydrophobic melamine sponge has the advantages that the preparation process is simple and convenient, the conditions are mild, and the adjustment and control of hydrophobic performance of the super-hydrophobic melamine sponge can be achieved by changing the concentration of a 1H, 1H, 2H, 2H-perfluorododecane mercaptan solution during the preparation.